We're going to turn to the breaking news overnight from egypt. A long-time u.S. Ally now in chaos. We got word that 500 people have been killed, thousands injured in the military crackdown on political protesters. This morning, there are fears this violence could spread beyond egypt and jeopardize america's security. Muhammad lila is on the scene in cairo. Good morning, muhammad. Reporter: Good morning to you, george. This entire city is on-edge, now living under martial law, with more people bracing for even more violence. It's the aftermath of what's being called a massacre. This entire neighborhood seen in the country's worst violence in years, is still smoldering this morning, after police attacked thousands of protesters, setting the entire area on fire. Fierce battles that paralyzed the city. Driving through streets that are now deserted, it's clear that today, the military is in charge. Banks, railroads and the country's stock exchange are still closed, with most of the country living under a curfew and martial law. Some blame the country's muslim brotherhood for the country's descent into violence. But many here blame the united states. Egypt is a key u.S. Ally. The most populous nation in the middle east. Receiving more than $1 billion in foreign aid. There's concern of a ripple effect. The violence could spread beyond egypt, with people targeting americans and american interests across the middle east. And, george, just to give you a sense of the uneasiness here. This is a prime tourist location. Normally, the nile river would be covered in boats and you would find tourists, including americans, out for a stroll. Take a look today, nothing. And that's because people are so afraid, they're not even going outside.

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